1. Field of The Invention
The present invention relates generally to an information forming system having a toner recovering function of recovering a toner remaining on a surface of a photosensitive material drum after transferring an image to a paper, a waste toner container for accumulating a recovered waste toner, and a toner container used in connection with the recovery of the toner.
2. Description of the Related Background Art
In image forming systems, such as copying machines, facsimiles and printers, a photosensitive material drum is electrified to be exposed in accordance with an image, and a toner is absorbed onto the photosensitive material drum to carry out developing for forming a visible image. After this visible image is transferred to a transfer paper, fixing is carried out by heating, so that a desired copy is obtained.
After the transfer to the transfer paper, excessive toner remains on the photosensitive material drum. Since such a toner remaining on the photosensitive material drum has an adverse influence on the next copying, the remaining toner must be completely removed.
In order to remove such a remaining toner after fixing, a cleaner is conventionally provided. This cleaner has a de-electrifier for de-electrifying the photosensitive material drum before cleaning, and a blade for raking down the toner on the photosensitive material drum. The toner removed by the de-electrifier and the blade is housed in a container called a waste toner box. These are known generally as a toner recovery unit.
A conventional waste toner box must have a sufficient size since a waste toner introduced into the toner box via an inlet naturally drops to accumulate therein.
Describing this point in detail, FIG. 5 shows the state that waste toner accumulates in a waste toner box. This waste toner box 20 has a laterally elongated flat box shape. Only a right end portion 20a of the waste toner box 20 rises so as to approach the above described cleaner portion. An opening 20b is formed in the top of the right end portion 20a. The toner raked down by the blade of the cleaner is introduced into the opening 20b by means of a suitable guiding portion (not shown) to be housed in the waste toner box 20.
As described above, since the accumulation of the waste toner is carried out by the natural drop via the opening 20b, the waste toner is sequentially accumulating in the waste toner box, so that the accumulation has a substantially conical shape as shown by a curved solid line a.
Therefore, if the top end of the accumulation approaches the opening 20b as shown in FIG. 5, the waste toner can not further accumulate although a space for accumulation remains as a whole.
To solve this problem, conventionally, a sensor comprising a light emitting element 22 and a light receiving element 23 is provided for monitoring the filling state of the toner. If it is detected by the sensor that the height of the accumulation of the waste toner exceeds a predetermined height, an alarm is produced to allow the operator to shake the waste toner box 20 or the like to flatten the top of the waste toner as shown by a curved line b, or to continue a copying operation after the waste toner box is exchanged.
In addition, conventionally, it is supposed that the waste toner box is not frequently exchanged, and the waste toner box must have a large capacity since the above described accumulation of the toner is carried out. This deteriorates the degree of freedom of design, or prevents the miniaturization of the system.
On the other hand, toners supplied to image forming systems have been improved as important components for enhancing the quality of an image, and manufacturers have provided the optimum toners for the design specification of their systems as genuine products (which will be hereinafter referred to as "certified products").
In recent years, toners meeting the minimum specifications common to image forming systems commercially available from a plurality of manufacturers are in circulation. There is a problem in that such toners meeting only a part of specifications (which will be hereinafter referred to as "uncertified toners") generally have inferior image quality and have a bad influence on a photosensitive material drum serving as an image carrier and a developing part, to adversely effect the reliability of the systems.
A typical toner is generally housed in a container to be provided. Conventionally, although toners have been sometimes improved to be easily handled, toners have not often been improved to recommend the certified products.
In particular, although the above described waste toner box is closely related with a toner cartridge, the waste toner box and the toner cartridge are separately attached or exchanged, and there is a problem in that the waste toner box can be used whether the toner cartridge is a certified product or an uncertified product.